Filmstrip takeup

ABSTRACT

An improved filmstrip guide includes an edge abutment surface and an outside guide surface for conforming a filmstrip to the surface of an imaginary cone from which the strip is steered into a coil in an open-ended cylindrical container. The edge abutment surface extends inward from the cone surface and follows a helix on the cone that is a straight line in a development of the cone. The outside guide surface lies on the cone surface next to the edge abutment surface, and both guide surfaces extend about 180* around the cone and terminate near the open end of the container. The cone&#39;&#39;s rays generally pass through the space inside the coil, and the cone diameter in the plane of the open end of the coil is less than the inside diameter of the coil.

mite ts i 1 amaze Primary Examiner-Billy S. Taylor fittorneyCumpston,Shaw & Stephens ABSTRACT: An improved filmstrip guide includes an edgeabutment surface and an outside guide surface for conforming a filmstripto the surface of an imaginary cone from which the strip is steered intoa coil in an open-ended cylindrical con tainer. The edge abutmentsurface extends inward from the cone surface and follows a helix on thecone that is a straight line in a development of the cone. The outsideguide surface lies on the cone surface next to the'edge abutmentsurface, and both guide surfaces extend about 180 around the cone andterminate nwr the open end of the container. The cones rays generallypass through the space inside the coil, and the cone diameter in theplane of the open end of the coil is less than the inside diameter ofthe coil.

PATENTED SEP 71971 swim mulluu-uulaumnn I N VE N TOR. ROBERT IV.MCFADDEA/ HIS ATTORNEY PATENTED SEP H971 SHEET H UF 2 m c fi M mm 270" 5ELSE; 15: 9:95;, 1 9.11 9:. BAP P; P. P fly UIJUIJIJIJ DUUDEIDUUBDHUUUNIO I N VE N TOR. ROBERT N. MCFADDEA/ HIS ATTORNEY This inventionrelates to a filmstrip takeup of the type in which a filmstrip is pushedinto a coil in an openended, cylindrical container, and moreparticularly to an improved guide for steering the film accurately intoa coiled configuration in the container with minimum resistance.

in prior art film talteups of this general type, a filmstrip was guidedaround a cylindrical surface on the axis of the desired coil and wasmade to follow a variable helix, of decreasing pitch as the filmstripapproached the container. The container was generally a rotatablecylinder holding a conventional film can. The leading end of thefilmstrip was intended to emerge from the cylindrical guide helix andenter the can, and as the film pressed against the bottom of the can,the interference or back pressure from the can accomplished the finalstep of conforming the film strip to a cylindrical coil inside the can.

customarily, the instructions for operating such a prior art filmstriptalteup suggested that the can be manually rotated in the direction ofthe coiling of the filmstrip as the first turn of the coil was beingformed to insure that the filmstrip was properly started in its coil. ifthis was not done, the filmstrip could jam against the bottom of thefilm can with sufficient force to tear its sprocket holes. Also, suchprior art takeups could not be operated withoutthe film can arrangedinside the rotatable container to receive the filmstrip coil, and theywere not effective in coiling filmstrips with unusual curl conditions.The curling tendencies of filmstrips vary widely with the make and sizeof film, temperature, humidity, and previous curling experience. Manualintervention in the talteup was often necessary to start the coiling ofsome filmstrips, and filmstrips with a coil tendency reverse to thenormal could even miss the receiving film can completely.

The objects of this invention include, without limitation, overcomingthe deficiencies of prior art film talteups of the type described, andguiding a filmstrip into a cylindrical coil in an open'cnded cylindricalcontainer so that:

a. no manual intervention is required;

is. any of a variety of films and film curling tendencies can beaccommodated, including either normal or reverse curl;

c. the guiding is smooth, low friction, consistent, and accurate;

d. a minimum of force is needed to push the film into the container;

e. the guide path is short and the guide is compact;

f. the film is not scratched or damaged and has minimum contact with theguide; and

g. the guide is economically manufactured and maintained and iscompetitive with prior art guides.

These and other objects of the invention will be apparent hereinafterfrom the specification which describes the invention, its use,operation, and preferred embodiment from the drawings, which constitutea part of the disclosure, and from the subject matter claimed.

Generally, the improved guide for directing a pushed filmstrip into acoiled configuration in an open-ended cylindrical container includes thefollowing features: an edge abutment surface for guiding the edge of thefilmstrip, the charactcristics of such edge abutment surface being thatit follows a helix on an imaginary conic surface substantially all therays of which extend through the space inside the coil, that it extendsinward from the conic surface, that it is a substantially straight linein a development of the conic surface, that it terminates near the openend of the container; and an outside guide surface adjacent the edgeabutment surface and lying approximately on the conic surface forconforming the filmstrip generally to the conic surface. By such anarrangement, the filrnstrip is guided around the conic surface until itsleading edge approaches a parallel relation with the axis of the coiland the film is turned to a diameter iess than the inside diameter ofthe coil. Filmstrips of any curling tendency, when conformed to such anorientation by the inventive guide, are automatically steered with aminimum of resistance into the desired coil. in the Drawings FlG. i is aplan view of the inventive film takeup;

PM]. 2 is an end elevation ofthe film takeup of HG. ll;

H6. 3 is a partially cutaway side elevation of the film takeup of FIG.ll;

FIG. 4 is a partially schematic side sectional view of the filmstrippath for the takeup of HG. i; and

HO. 5 shows a development of the guide surfaces of the film talteup ofH6. 1.

The illustrated preferred embodiment of the invention will be describedbriefly, and then some of the considerations for constructing filmguides according to the invention will be explained. Throughout thedrawings, corresponding parts have the same reference numbers.

The illustrated film takeup was designed for a projector using a35-millimeter filmstrip, and some configurations of the takeup areinfluenced by projector design rather than the essentials of theinvention. The inventive takeup can be used for other widths offilmstrip and other photographic equipment. For convenience, theinvention will be described relative to the illustrated embodiment, butthose skilled in the art will un derstand that other embodiments andarrangements of the inventive takeup are possible.

Filmstrip it) is advanced by sprocket ill into guide ill which bendsfilmstrip Mi so as to wrap it around the surface of an imaginary cone2!, the vertex of which is aimed generally into container 13. Containeri3 has a hub lid that is rotatably housed in a bearing 15, so thatcontainer 13 can rotate freely. A conventional film can 20 can be placedloosely inside con tainer if; for rotation therewith to receivefilmstrip it), Filmstrip lltl is coiled in either can 20 or container 13so that the outermost convolution of the coil is formed by the leadingportion of filmstrip MB and successive convolutions are laid inside thepreceding outer convolutions as filmstrip it) is taken up. This leavesthe leading end of filmstrip it) lying on the outside of the completedcoil and ready for reprojection without rewinding.

For some purposes, it is preferred not to rccoil filmstrip it), andcontainer 13 is pivoted aside so that filmstrip it can be led pastcontainer 13 and outside the projector. Such an arrangement can be usedfor continuous loop projection, for example, or for any filmstrip thatis too long to coil inside container l3. Container l3 also pivots asidefor insertion and removal of film can 20. Such pivoting aside ofcontainer ll} is accomplished by a frame Mi supporting bearing 15 andcontainer i3 and pivotally mounted on pin 27. Pivoting of frame to onpin 17 in the direction of the arrow in FIGv ll moves container 13 outof the path of filmstrip it). A latch ridge lid on frame id is arrangedto engage a resilient latch means (not shown) on the projector forholding container 13: in a pivotedaside position, and a lever w isarranged for moving container R3 between positions.

The axes of container 113 and imaginary cone 21 are each oblique to thepath of filmstrip it? as it leaves sprocket it. Conic surface Trill canbe thought of as containing an infinite number of rays each of which isan imaginary line on the sur face of cone M in a plane with the coneaxis and extending through the vertex of the cone. All the rays of cone2ll extend through the space inside the coil which filmstrip it) formsin can 2% and cone 2f is preferably, but not necessarily, a rightcircular cone. Filmstrip it) is preferably turned on cone 21 to asmaller diameter than the inside diameter of its intended coil, and thisis effected by cone 2i having a smaller diameter in the plane of theopen end of film can 20 than the coil to be formed by filmstrip it)inside film can 2t).

Guide ll2 has two principal guide surfaces that conform filmstrip lld tothe desired conic shape. These guide surfaces are an edge abutmentsurface 25, and an outside guide surface 26, each of which followimaginary conic surface 211i.

Edge abutment surface 25 follows a helix on conic surface Eli andextends inwardly from conic surface 23 and outside guide surface 26.Edge abutment surface 25 is a substantially straight line in adevelopment of the imaginary conic surface 21, as shown in FIG. 5. Also,edge abutment surface 25 terminates at its output end in the region ofthe open end of film can 20.

Outside guide surface 26 lies adjacent edge abutment surface 25 and onthe surface of cone 21. Outside guide surface 26 preferably extends pastthe perforation holes in filmstrip 10 to the edge of the picture area offilmstrip 10, a distance somewhat less than one-quarter of the width ofstandard filmstrips. Outside guide surface 26 thus preferably forms thetop of a raised ledge engaging the perforated margin area of filmstrip10 which is stiffenough to be conformed to the surface of imaginary cone21 by such engagement. Restricting outside guide surface 26 to themarginal edge of filmstrip 10 outside the picture area insures that thepicture area of filmstrip 10 will not be scratched in passing throughguide 12. However, outside guide surface 26 can extend further acrossfilmstrip 10, or all the way across filmstrip 10, if desired.

Surface 27 of guide 12 adjacent outside guide surface 26 is preferablyrecessed relative to guide surface 26 to lie slightly beyond or outsidethe surface of imaginary cone 21. Filmstrip l0, and particularly theleading end of filmstrip 10, is restrained by surface 27 from anysubstantial deviation from the conic configuration to which it isconformed principally by outside guide surface 26. However, in normaloperation, filmstrip 10 does not engage surface 27.

An entry guide surface 28 generally opposite guide surface 26 insuresthat the leading end of filmstrip 10 is directed into engagement withoutside guide surface 26 and edge abutment surface 25 and prevents anycurling of filmstrip 10 completely away from guide 12. For the samepurpose, guide 12 is preferably positioned near sprocket 11.

The terminal or output end of outside guide surface 26 is preferablycutaway or beveled to form a discharge surface 29 extending obliquelyoutward from the surface of imaginary cone 21. This eliminates any filmscratching edge at the output end of guide 12 and allows filmstrip 10 tobe guided slightly upward and away from guide 12 when it is not beingformed into a coil in can 20.

Guide 12 is preferably molded of a single piece of plastic material andarranged as illustrated relative to container 13.

FIG. shows a development of the imaginary cone 21 to represent edgeabutment surface 25 and outside guide surface 26 as rolled out flat in aplane. Edge abutment surface 25 is a straight line in such development,and outside guide surface 26 and discharge surface 29 are clearly shownrelative to filmstrip 10.

In operation, the leading end of filmstrip is driven past sprocket 11and into the input end of guide 12. The guided edge of filmstrip engagesoutside surface 26 and edge abut ment surface 25 and is bent to conformto the surface of imaginary cone 21. At the output end of guide 12, theleading end of filmstrip 10 is approximately in the position illustratedin broken lines in FIGS. 1 and 3. Depending on the curl of filmstrip 10,its leading end may point upward as shown by the upper broken lineposition in FIG. 2, or may tend to curl on around the surface of cone 21as shown by the lower broken line position in FIG. 2. In either case,the leading end of filmstrip 10 is directed into can in a path such thatit forms the coil illustrated in FIG. 4 automatically with the leastpossible resistance. The turning or bending of filmstrip 10 by guide 12is acute enough to impress a conic shape into filmstrip 10 so thatregardless of variations in the curl of filmstrip 10 it isadvancedautomatically into the coil shown in FIG. 4.

Several general considerations such as film characteristics, coil siie,etc. affect'the size and shape of guide 12 and its orientation relativeto the film path at sprocket 11 and takeup container 13. These generalconsiderations are also influenced by the design requirements of aprojector or other photographic equipment using the inventive takeup.Such considerationsi are discussed in the following paragraphs.

Takeup' container 13 is preferably angled obliquely to the path offilmstrip 10 leaving sprocket 11. A takeup container aligned with thefilmstrip path would require the filmstrip to be conformed to along,thinly tapered cone with the filmstrip guided almost to the vertex ofthe cone before entering a coil in the container. A container anglednearly normal to the filmstrip path would require that the filmstrip beconformed to a fairly large diameter cone so that the turned-over,leading end of the filmstrip could clear the edge of the filmstripopposite the edge being guided. This tends to require either a lengthguide or a relatively large diameter coil and receiving container. Thespace available within the photographic equipment to accommodate variousoblique container angles relative to the film path, and the spacerequired for pivoting the takeup container aside of the filmstrip, ifdesired, also effect guide and container angles.

The inside diameter of the film coil to be formed in the takeupcontainer is generally determined by the length of filmstrip to becoiled within a standard size film can. Generally, the guide path shouldbe as short as feasible so that the filmstrip engages the guide for aminimum length of travel. The diameter of the imaginary cone in theplane of the open end of the film can or other container is preferablyless than the inside diameter of the coil to be formed so that theinnermost convolution of the filmstrip is laid inside such coil withoutinterference. Preferably, the guide is arranged near the coil receiverso that the filmstrip does not make any substantial unguided traversebetween the guide and the receiver. Also, the curvature impressed on thefilmstrip by the guide is preferably acute enough to insure that anyadverse coiling tendencies of the filmstrip are overcome and thefilmstrip is faithfully conformed to the surface of the imaginary cone.

At the entry of the guide, the filmstrip can intersect the rays of theguide cone at various oblique angles depending on length of the path ofthe filmstrip around the cone and the position of the coil-receivingcontainer. As the filmstrip proceeds toward the output end of the guide,the angles between its edges and the cone rays become larger andapproach the perpendicular. The optimum transition point for thefilmstrip to turn from the conic surface into a cylindrical coil isalong the line of the cone ray normal to the edges of the filmstrip.From such a line, the filmstrip can leave the conic surface on a tangentand enter a coil whose axis is parallel with the transition ray withoutany lateral turning of the film. Whether the film guide surfaces shouldextend all the way to the transition line depends in part on otherparameters and the possibility of optionally leading the filmstrip asideof the container without forming a coil.

With such considerations, variables, and objects in mind, the preciseconfiguration and orientation of guide 12 and container 13 was reachedsomewhat in the following manner. A 35-millimeter filmstrip, a standard35-millimeter film can, and a 60 frame length of filmstrip were given.These determined the inside diameter of the coil of filmstrip in can 20and incidentally allowed a frame length of filmstrip 10 to be coiled tothe same inside diameter in container 13. Projector considerations alsodetermined the side of the film path on which container 13 would beobliquely positioned, and decreed that the container be pivotal forleading filmstrip 10 past container 13 without coiling. Also, the normalcoil tendency of filmstrip 10 as oriented in the projector determinedthat the guide 12 should bend the filmstrip upward and over cone 21toward the right of the film path as illustrated. An approximate turn orhalfway traverse around cone 21 then brings filmstrip 10 to the top ofcone 21 from whence it can be led sideways out of the projector orguided into the desired coil, so that a 180 turn around cone 21 wasselected as optimum for the length of guide 12.

Filmstrip 10 tends to continue in the conic path to which it isconformed by guide 12 after leaving the output end of guide 12, and afurther one-fourth turn around cone 21 was selected as the optimumtransition point for filmstrip 10 to turn from its conic path to acylindrical path inside film can 20. Thus, a 270 turn around cone 21 waschosen as the optimum conic transverse for coiling filmstrip 10, andafter a 270 turn around cone Jill the square-cut leading end offilmstripW was arranged to be substantially parallel with the axis of containerl3, and the intersected ray of cone Ell. From such a position, filmstripl can leave cone 2i tangentially and form a cylindrical coil without anylateral turning.

The inside diameter of the coil of Filmstrip 110 in a standard film cangive the maximum circumference C of cone Fill in the plane of the openend of the film can so that the innermost convolution of the coil can beguided into the film can without interference.

Edge abutment surface 25 is preferably a straight line in thedevelopment of cone 21 so that the edge of filmstrip l0 can followabutment surface 25 naturally without buckling or distortion.

With these determinations made, the development of guide l2 as shown inP16. 5, is constructed as follows. Since the leading edge of filmstripl0 is normal to edge abutment surface 215 and preferably parallel withan intersected ray of cone 2i after 270 of turning around cone 211, aray line 31 is constructed normal to the extension of the line ofabutment surface 25 at 270 of cone wrap. One-fourth of circumference Cis measured back along the extension of edge abutment sur face 255 tomark the output end of guide l2 at the 180 mark of cone wrap, and line32 is normal to surface 25 at such point. One-half the circumference Cis then measured back from line to determine the desired length of edgeabutment surface 33 and outside guide surface 2t, and a line 33 marksthe input end of guide l2. Then, the angle between container l3 and thepath of film W at sprocket lit, and the desired sharpness of curvaturefor guide if! determine entry angle E which is constructed at 0 line 33.Line 3 is then extended at angle E to represent a ray of the cone 211 atthe entry to guide 12, and the intersection of line 34 with line 311determines the vertex V of cone 2B. The angle l3 between line 3d andedge abutment surface 25 is the helix angle ofentry defined as the anglebetween edge abutment surface 25 following the desired helix and the rayintersected at the entry of filmstrip iltll into guide 10;. The helixangle between edge abutment surface 25 and successive rays approachingthe output ray 35 is progressively greater. The ray 3ll at the extensionof cone Illll to 270 of turn is normal to the helix followed byfilmstrip l0 and marks the transition point at which filmstrip 10 canassume a cylindrical coiled configuration without turning from its path.At the 180 mark or output end of guide E2, the leading end of filmstripl0 approaches a parallel relation with ray 35 and is nearing thetransition point.

The 270 transition ray 31 is shown in broken line in FllG. ll toillustrate the preferred relationship of filmstrip 1 .0 to takeupcontainer l3 at such point.

The cone developed in HG. is preferably aimed relative to container if)so that the vertex is near the axis of container l3 and the rays of thecone extend through the inside of the coil formed in can 20. As bestshown in FIG. 3, in the illustrated embodiment of the invention a raylying at the bottom center of cone is approximately tangent to theinside of the coil to be formed in can 20.

For optimum balancing of the various design considerations, it ispreferred that entry angle E be more than 30 and preferably about 45.Also, it is preferred that the helix angle between abutment surface 25and the ray 35 intersected at the output end of guide ll! be less than30, and preferably less than 20.

Edge abutment surface 25 is preferably normal to the sur face of cone21, but can be acute or stand inward at some angle other than normal, solong as it provides a firm edge support for filmstrip it).

It will thus be seen that the inventive takeup guide accomplishes theabovestated objects of the invention. Filmstrip can follow edge abutmentsurface 25 without any buckling or transverse curvature and can beconformed to a conic surface by outside guide surface 2 h with a minimumof friction and with freedom from scratching the picture area offilmstrip l0. Guide l2 is short, smooth, accurate, and capable ofconforming a filmstrip of any curling tendency into a conic shape foraccurate coiling into a takeup container. No manual intervention isnecessary, and the inventive takeup is economical, simple, accurate, andcompetitive.

Other features, advantages, and other specific embodiments of thisinvention will be apparent to those exercising ordinary skill in thepertinent art after considering the foregoing disclosure. in thisregard, while specific preferred embodiments have been described indetail, such disclosure is intended as il lustrative, rather thanlimiting, and other embodiments, variations, and modifications can beeffected within the spirit and scope of the invention as disclosed andclaimed. Furthermore, the following claimed subject matter is intendedto cover fully all the aspects of the disclosed invention that areunobvious over prior art, including all equivalent embodiments.

lclaim:

1. In a filmstrip takeup having a generally cylindrical, open endcontainer for receiving said filmstrip in a coiled configuration andmeans for pushing said filmstrip generally toward said open end of saidcontainer, an improved guide for directing said filmstrip into saidcoiled configuration in said container, said guide comprising:

a. an edge abutment surface for engaging and guiding an edge of saidiilmstrip;

1. said edge abutment surface being configured to follow a helix on animaginary conic surface substantially all the rays of which extendthrough the space inside said coil;

2. said edge abutment surface extending inward from said conic surface;

3. said edge abutment surface being a substantially straight line in adevelopment of said conic surface;

4. the output end of said edge abutment surface terminating in theregion of said open end of said container; and

b. an outside guide surface adjacent said edge abutment surface andformed to lie approximately on said conic surface for conforming saidfilmstrip generally to said conic surface with an edge of said filmstripguided by said edge abutment surface.

2. The filmstrip takeup of claim ll wherein the diameter of said conicsurface in the plane of said open end of said container is less than theinside diameter of said coil.

3. The filmstrip takeup of claim l wherein a ray of said conic surfaceis substantially parallel with the axis of said coil and approximatelytangent to the inside of said coil.

4. The filmstrip takeup of claim ll wherein said edge abutment surfaceand said outside guide surface extend approximately around said conicsurface.

5. The filmstrip takeup of claim ll including means for pivot ing saidcontainer aside from said conic surface, and said out side guide surfaceis cut away at said output end for leading said filmstrip past saidcontainer.

6. The filmstrip takeup of claim it wherein said guide surface is lessthan onc-fourth of the width of said filmstrip.

'7. The filmstrip takeup of claim ll wherein said guide sur face issubstantially as wide as said filmstrip.

ill. The filmstrip takeup of claim 1 wherein a surface adjacent saidguide surface is depressed from said conic surface for a major portionof the width of said filmstrip.

9. The filmstrip takeup of claim ll wherein the angle of said helix ofsaid edge abutment surface to a ray of said conic surface intersected atsaid output end of said guide is less than 30.

W. The filmstrip takeup of claim ll wherein the angle of said helix ofsaid edge abutment surface to a ray of said conic surface intersected atthe input end of said guide is more than 30.

ill. The tilmstrip takeup of claim ll wherein the angle of said helix ofsaid abutment surface to a ray of said conic surface intersected at theoutput end of said guide is less than 20.

E2. The filmstrip takeup of claim l including a surface disposedopposite said outside guide surface for directing the leading end ofsaid films-trip into engagement with said edge abutment surface and saidoutside guide surface.

13. The filmstrip takeup of claim ll wherein said edge abutmcnt surfaceis approximately normal to said conic surface.

14. The filmstrip takeup of claim 1 wherein the path of said filmstripat the input end of said guide is oblique to the axis of said container.

15. The filmstrip takeup of claim 14 wherein said guide surface is lessthan one-fourth of the width of said filmstrip.

16. The filmstrip takeup of claim 15 wherein the angle of said helix ofsaid edge abutment surface to a ray of said conic surface intersected atsaid output end of said guide is less than 30.

17. The filmstrip takeup of claim 16 including a surface disposedopposite the outside guide surface for directing the leading end of saidfilmstrip into engagement with said edge surface intersected at theinput end of said guide is more than 30, and the diameter of said conicsurface in the plane of said open end of said container is less than theinside diameter of said coil.

19. The filmstrip takeup of claim 18 wherein a ray of said conic surfaceis substantially parallel with the axis of said coil and approximatelytangent to the inside of said coil.

20. The filmstrip takeup of claim 19 wherein said edge abutment surfaceis approximately normal to said conic surface, and said edge abutmentsurface and said outside guide surface extend approximately around saidconic surface.

21. The filmstrip takeup of claim 20 including means for pivoting saidcontainer aside from said conic surface, and said outside guide surfaceis cutaway at said output end for leading said filmstrip past saidcontainer.

1. In a filmstrip takeup having a generally cylindrical, open endcontainer for receiving said filmstrip in a coiled configuration andmeans for pushing said filmstrip generally toward said open end of saidcontainer, an improved guide for directing said filmstrip into saidcoiled configuration in said container, said guide comprising: a. anedge abutment surface for engaging and guiding an edge of saidfilmstrip;
 1. said edge abutment surface being configured to follow ahelix on an imaginary conic surface substantially all the rays of whichextend through the Space inside said coil;
 2. said edge abutment surfaceextending inward from said conic surface;
 3. said edge abutment surfacebeing a substantially straight line in a development of said conicsurface;
 4. the output end of said edge abutment surface terminating inthe region of said open end of said container; and b. an outside guidesurface adjacent said edge abutment surface and formed to lieapproximately on said conic surface for conforming said filmstripgenerally to said conic surface with an edge of said filmstrip guided bysaid edge abutment surface.
 2. said edge abutment surface extendinginward from said conic surface;
 2. The filmstrip takeup of claim 1wherein the diameter of said conic surface in the plane of said open endof said container is less than the inside diameter of said coil.
 3. Thefilmstrip takeup of claim 1 wherein a ray of said conic surface issubstantially parallel with the axis of said coil and approximatelytangent to the inside of said coil.
 3. said edge abutment surface beinga substantially straight line in a development of said conic surface; 4.the output end of said edge abutment surface terminating in the regionof said open end of said container; and b. an outside guide surfaceadjacent said edge abutment surface and formed to lie approximately onsaid conic surface for conforming said filmstrip generally to said conicsurface with an edge of said filmstrip guided by said edge abutmentsurface.
 4. The filmstrip takeup of claim 1 wherein said edge abutmentsurface and said outside guide surface extend approximately 180* aroundsaid conic surface.
 5. The filmstrip takeup of claim 1 including meansfor pivoting said container aside from said conic surface, and saidoutside guide surface is cut away at said output end for leading saidfilmstrip past said container.
 6. The filmstrip takeup of claim 1wherein said guide surface is less than one-fourth of the width of saidfilmstrip.
 7. The filmstrip takeup of claim 1 wherein said guide surfaceis substantially as wide as said filmstrip.
 8. The filmstrip takeup ofclaim 1 wherein a surface adjacent said guide surface is depressed fromsaid conic surface for a major portion of the width of said filmstrip.9. The filmstrip takeup of claim 1 wherein the angle of said helix ofsaid edge abutment surface to a ray of said conic surface intersected atsaid output end of said guide is less than 30*.
 10. The filmstrip takeupof claim 1 wherein the angle of said helix of said edge abutment surfaceto a ray of said conic surface intersected at the input end of saidguide is more than 30*.
 11. The filmstrip takeup of claim 1 wherein theangle of said helix of said abutment surface to a ray of said conicsurface intersected at the output end of said guide is less than 20*.12. The filmstrip takeup of claim 1 including a surface disposedopposite said outside guide surface for directing the leading end ofsaid filmstrip into engagement with said edge abutment surface and saidoutside guide surface.
 13. The filmstrip takeup of claim 1 wherein saidedge abutment surface is approximately normal to said conic surface. 14.The filmstrip takeup of claim 1 wherein the path of said filmstrip atthe input end of said guide is oblique to the axis of said container.15. The filmstrip takeup of claim 14 wherein said guide surface is lessthan one-fourth of the width of said filmstrip.
 16. The filmstrip takeupof claim 15 wherein the angle of said helix of said edge abutmentsurface to a ray of said conic surface intersected at said output end ofsaid guide is less than 30*.
 17. The filmstrip takeup of claim 16including a surface disposed opposite the outside guide surface fordirecting the leading end of said filmstrip into engagement with saidedge abutment surface and said outside guide surface.
 18. The filmstriptakeup of claim 17 wherein the angle of said helix of said edge abutmentsurface to a ray of said conic surface intersected at the input end ofsaid guide is more than 30*, and the diameter of said conic surface inthe plane of said open end of said container is less than the insidediameter of said coil.
 19. The filmstrip takeup of claim 18 wherein aray of said conic surface is substantially parallel with the axis ofsaid coil and approximately tangent to the inside of said coil.
 20. Thefilmstrip takeup of claim 19 wherein said edge abutment surface isapproximately normal to said conic surfacE, and said edge abutmentsurface and said outside guide surface extend approximately 180* aroundsaid conic surface.
 21. The filmstrip takeup of claim 20 including meansfor pivoting said container aside from said conic surface, and saidoutside guide surface is cut away at said output end for leading saidfilmstrip past said container.